Disposable Clothing

ABSTRACT

A disposable clothing is used for protection against liquids or microorganisms, in particular for medicine, chemistry or biotechnology. The clothing comprises, in particular a front part and sleeves ( 20 ) connected thereto. The clothing ( 10 ) is provided with an external layer ( 12 ) in the form of a non-woven air-permeable material. A barrier layer which is selected such that it is air permeable but liquid-proof, is applied to at least the side of the external layer ( 12 ) which is oriented towards a person wearing the clothing ( 10 ). The barrier layer is, at least in places, connected to the external layer. The non-woven material of the external layer ( 12 ) is a laminated material comprising spunbond and meltblown layers.

This application is a continuation of Ser. No. 10/532,624 filed Dec. 29,2005 as the national stage of PCT/EP2003/011869 filed on Oct. 25, 2003and also claims Paris Convention priority of DE 102 50 275.7 filed onOct. 28, 2002 the entire disclosures of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

The invention concerns a disposable piece of clothing, in particular,for medical, chemical or biochemical use to provide protection againstliquids and/or microorganisms, comprising a front part and sleeves whichare integrally connected thereto. The piece of clothing may moreovercomprise a back part and have, in particular, the shape of a coat.Clothing of this type may be made from an air-permeable non-wovenmaterial, wherein reinforcements may be provided in some regions tofurther improve the barrier that stops penetration of liquids andmicroorganisms.

EP 0 560 376 B1 describes e.g. a piece of clothing with an outer layerof a densely woven hydrophobic fabric forming a liquid and microorganismbarrier and a carrier material with a net-like structure having openingsor open meshes, wherein a diaphragm is provided as third layer on thiscarrier material at critical locations with regard to penetration ofliquid or microorganisms.

EP 0 797 505 B1 discloses a piece of clothing with mounted barrierlayer, wherein the barrier layer arrangement is thereby applied onto thematerial substrate as a thin, flexible polymer layer in an additionalprocessing step. The barrier layer sheet is applied from the outer side.

U.S. Pat. No. 4,504,977 describes use of hydrophobic andwater-impermeable barriers in connection with clothing fabric, inparticular, for surgical coats to prevent penetration of water oraqueous solutions. It proposes use of a coat comprising a layer ofhydrophobic non-woven fabric with air voids which consists of micro-finehydrophobic fibers. Clothes of this type which are preferably worn bypersons who work in the medical or chemical field, must provide highcomfort during wear even over longer periods and also form a safebarrier against substances, e.g. liquids and microorganisms, inparticular, bacteria. In critical areas which are subject to great wearand to intensive substance exposure, e.g. which come in contact with thepatient's blood, the substances may penetrate through the clothing. Forthis reason, a water-impermeable sheet is provided in the breast regionthat is completely impermeable to water vapour.

Further surgical coats with reinforced regions are disclosed e.g. inU.S. Pat. Nos. 3,868,728 and 5,813,052, the former disclosing adisposable coat and the later a reusable surgical coat.

In view of the above, it is the object of the invention to provide animproved piece of clothing for medical, chemical or biotechnological usewhich safely prevents penetration of liquid or bacteria for apredetermined time period and at the same time provides good comfort dueto its low intrinsic weight and comfortable wearing properties, inparticular, during relatively long wear under difficult conditions, e.g.for surgical operating staff.

SUMMARY OF THE INVENTION

This object is achieved by a disposable piece of clothing, inparticular, for medical, chemical or biotechnological use, as aprotection against liquids or microorganisms, comprising a front partand integrally connected sleeves, wherein the piece of clothingcomprises an air-permeable outer non-woven layer and wherein at leastregions of the side of the outer non-woven material facing the personwearing it, have an air-permeable and liquid-impermeable barrier layerwhich is connected, at least in sections to the outer layer, and whereinthe outer layer is a laminated material consisting of spunbond andmeltblown layers. Laminated material thereby means a layered compositematerial in the broadest sense. It may be formed through connecting twopre-fabricated layers and also e.g. through integral production of thelayered composite material e.g. such that one layer is generateddirectly through disposing previously produced fibers onto the furtherlayer.

The barrier layer provides, in a straightforward fashion, liquidimpermeability which cannot be obtained with conventional non-wovenmaterials, while maintaining air permeability.

In this manner, a particularly light material is moreover produced suchthat an operating coat of this type is especially comfortable to wear.

With particular advantage, the non-woven material is an inherentlyhydrophobic or liquid repellent spunbond/meltblown/spunbond (SMS) or aninherently hydrophobic or liquid repellent spunbond/meltblown material(SM) or also an inherently hydrophobic or liquid repellent SMMSmaterial. Laminated materials of this type, in particular, ofpolypropylene are advantageous in that they are particularly soft. Allthree layers of an SMS laminated material preferably consist e.g.substantially of polypropylene and are consequently each inherentlyhydrophobic or liquid repellent. Further auxiliary substances such ase.g. antioxidants may be provided. The layers permit passage of air,water vapour and heat, while obstructing passage of germs and liquids.Other spunbond-meltblown laminated materials than those mentioned abovecan also be used.

Laminated materials of this type moreover form only small amounts offluff, despite their soft surface. The meltblown layer of microfibersthereby form a selective barrier. Moreover, laminated materials of thistype have good tearing strength.

A non-woven sheet laminated material may be provided for the barrierlayer, wherein the sheet may be a polyethylene sheet filled, inparticular, with calcium carbonate or other organic and/or inorganicfillers to form micropores and to provide air permeability in sheetswhich are usually not air-permeable, while maintaining the liquid andcontamination barrier. The sheet may additionally be mechanicallyfinished, in particular, be drawn or rolled to generate porosity.

The barrier layer may preferably be connected to the non-woven material,in particular, in a material-bonding manner, i.e. via glue or weldingconnections, such as thermal welding or ultrasound welding. Theconnection between the two materials does not thereby impair the densityor the wearing comfort, which could be the case with seamed connectionsvia sewing or through use of buckles or eyelets. If non-woven sheet,laminated materials are used as a barrier layer, the barrier layer maybe a sheet mounted between the spunbond-meltblown laminated material andthe outer non-woven material of the non-woven laminated sheet such thatthe non-woven material of the barrier layer, having the comfortabletactile properties, faces the person wearing the piece of clothing.

Barrier layer reinforcement may thereby be provided in the region of thesleeves, in particular, of the lower sleeve ends in the region of thehands to beyond the elbows and/or in the region of the breast, whereinthe barrier layer may extend in the breast region to beyond the knee ofthe person wearing the piece of clothing, in particular, if he/she isstanding and/or sitting. Contamination in these areas, which aresubjected to the highest contamination exposures, is thereby safelyprevented, while further increasing the wearing comfort in the otherregions. The sleeves generally have knitted bands at the ends facing thehands, which are overlapped by gloves when used as operating coat andalso for chemical and biotechnological applications. The bands aredesigned such that they closely fit the arm to prevent sliding andexposure of the skin located between the gloves and the sleeves.

In addition to the above-described embodiment, according to which theouter layer of the entire coat comprises a non-woven material, inparticular, a non-woven laminated material of spunbond and meltblownlayers. In an alternative design, regions of the clothing may have anon-woven material of spunbond and meltblown layers as an outer layerand regions, in particular, in the region of the sleeves have an outerlayer which is formed e.g. by a non-woven sheet laminated material. Inaddition to non-woven sheet laminated material, materials other than anon-woven material which consists of spunbond and meltblown layers arealso feasible. The outer barrier layer in the region of the non-wovensheet laminated material may then be omitted.

In this case, a non-woven sheet laminated material is provided withparticular preference in the region of the sleeves, which has anon-woven material component made from spunbond and meltblown layers. Toensure air permeability, the sheet component of this non-woven sheetlaminated material may be a sheet which is filled with organic and/orinorganic fillers, providing it with micropores. This non-woven sheetlaminated material comprises with particular preference a hydrophobic orliquid repellent spunbond/meltblown/spunbond (SMS) or a hydrophobic orliquid repellent spunbond/meltblown (SM) or a hydrophobic or liquidrepellent spunbond/meltblown/meltblown/spunbond (SMMS) laminatedmaterial as the non-woven component. The non-woven sheet laminatedmaterial may thereby be used such that the non-woven component isdisposed on the side facing away from the person wearing the piece ofclothing.

The outer layer in a region of the coat, in particular, in the region ofthe sleeves may alternatively be a non-woven sheet laminated materialwhich is formed from several non-woven material components and a sheetcomponent. A non-woven sheet laminated material of this type preferablycomprises two non-woven components and a sheet. The non-woven componentspreferably comprise a non-woven material which consists of a laminatedmaterial comprising spunbond and meltblown layers. In a particularlypreferred manner, this non-woven sheet laminated material comprises ahydrophobic or liquid repellent spunbond/meltblown/spunbond (SMS) or ahydrophobic or liquid repellent spunbond/meltblown (SM) or a hydrophobicor liquid repellent spunbond/meltblown/meltblown/spunbond (SMMS)laminated material as non-woven component. The non-woven sheet laminatedmaterial may be formed in particular symmetrically with respect to thecentral layer. This means, in particular, the sheet may be the centrallayer, wherein the non-woven component is identically providedmirror-symmetrically on both sides of the sheet.

The use of such non-woven sheet laminated material, in particular, inthe region of the sleeves is advantageous since the production of thesleeves is particularly complex, and moreover material is reduced, inparticular, in the region of the overlappings between sleeve seams orwelding points. At the same time, a certain barrier effect can beobtained.

Moreover, an associated piece of clothing can have a back part and bedesigned, in particular, as a wrap-around or closed coat. Thewrap-around coat overlaps in the back such that the coat does not easilyopen and at the same time is easy to put on, while maintaining a sterilestate. The coat may also be designed as a closed coat which ispreferably used for short operations with little amounts of liquidinvolved and small infection risk. Further disposable operating clothescan also be designed in this manner. The outer non-woven material oranother material used in some regions, can be welded to prevent passageof liquid and bacteria through seams. The additional reinforcingmaterial, in particular, in the sleeves may initially be connected tothe non-woven material and the sleeve is brought into its final tubularshape through welding.

The seams, in particular, on the sleeves may be folded-over oroverlapping seams or combinations thereof to further improve protectionagainst entering liquid. The seams may additionally be closed by anadditional sheathing. Seams of this type are disclosed e.g. in EP 560376 B1.

The piece of clothing may be conventionally folded when not in use toensure sterile application.

The clothing should have a penetration resistance to water at thereinforced locations of ≧150 cm (measured according to EN 20 811) and,in particular of ≧200 cm.

The surface density should preferably be ≦90 g/m² and, in particular ≦80g/m² in the combined layers.

The water vapor permeability at the reinforced locations should finallybe preferably ≧2000 g/m² (measured according to DIN 53 122-1 (climateB)). Penetration of ethanol shall be prevented to at least 80%(corresponding to the test described below) and, in particular, to atleast 96%.

A piece of clothing of this type should, in particular, have a highpenetration resistance to water which is exemplarily explained by acomparison of SMS material, non-woven sheet laminated material, and bothlaminated materials together and, in particular, a material as used inthe Ultra operating coat of the Kimberly Clark firm. It consists of twolayers of a special SMS material at the reinforced locations as outermaterial and as barrier layer.

A simple SMS non-woven material has a surface density of approximately35 g/m². The non-woven material consists of 100% polypropylene. Thenon-woven sheet laminated material used comprises a sheet which consistsof polyethylene and calcium carbonate as filler and has a surfacedensity of approximately 38 g/m².

In contrast thereto, the double-layered material of Kimberly Clark has asurface density of 52 g/m² per layer.

The water penetration resistance of the individual materials and of theinventive combination was determined according to the EN 20 811standard. The non-woven material alone only had a small resistance of 36cm. The resistance of the non-woven sheet material was 216 cm. Thecombined material of outer layer and barrier layer can therefore providea water penetration resistance of 233 cm.

The Kimberly Clark material tested in comparison thereto, has showed avalue of approximately 133 cm.

A water vapor permeability test measured according to DIN 53 122-1(climate B) showed a water vapor permeability of 6,656 g/m² in 24 h forthe outer non-woven material alone. The barrier layer obtained a valueof 3,217 g/m² in 24 h which results in a water vapor permeability of2,341 g/m² in 24 h for the overall material consisting of the outernon-woven material and the barrier layer. The material of the KimberlyClark coat showed a permeability of 6,394 g/m² which correspondssubstantially to the permeability of the outer material of the inventiveclothing.

The inventive clothing also has very good alcohol repelling propertieswhich can be determined using the standard test INDA Ist 80.9-74 (R77)and also by the following further testing method:

Testing method for alcohol repelling properties of non-woven materials:

Test devices: pipettes Transparent glass or plastic plate Mirror LampReagents: The test liquids were prepared according to table 1 andnumbered consecutively.

TABLE Test solution (mixing ratio (%) Ethanol/demin. H₂O) Ethanol 96%*demin. H₂O** evaluation grade 0 100 0 10 90 1 20 80 2 30 70 3 40 60 4 5050 5 60 40 6 70 30 7 80 20 8 90 10 9 100 0 10 *denaturated ethanol 96%**demineralized water

Sample Preparation:

At least 2 specimens (approximately 200×200 mm) are required. They arestored in a climatic chamber for 4 h at a temperature of 20+/−2° C. andat a relative air humidity of 65+/−2%.

The test sample is flatly disposed onto a smooth horizontal glass orplastic plate.

The test is started with the test liquid with the lowest number (alcoholrepelling grade 0). A small drop (of a diameter of approximately 5 mm)is disposed onto the test sample at least three locations using thepipette. After 5 minutes, it is checked whether or not the test liquidhas penetrated into the test sample. If no penetration occurred withinthese 5 minutes, drops of the test liquid with the next higher numberare disposed at a bordering location onto the test sample which is againobserved after 5 minutes.

The test is continued until one of the test liquids penetrates throughthe test sample.

Two or more drops of the test liquid are simultaneously applied onto thespecimen.

Analysis:

The alcohol repelling grade of the non-woven material is the number ofthe test liquid with the highest number which has not penetrated throughthe non-woven material after 5 minutes.

Normally that penetration is decisive which shows complete or partialdarkening of the non-woven material directly below the test liquid,viewed from the rear side. The final point can often be determined byturning the test sample after the 5 minute interval.

Reference to standards: INDA standard test IST 80.9-74 (R77)

The simple non-woven material did not show any penetration up to 80%alcohol. The non-woven sheet material and the laminated material ofnon-woven sheet and outer non-woven material showed no alcoholpenetration up to 96%. The double SMS material of Kimberly Clark alsoshowed no alcohol penetration up to 96%.

Finally, tests with blood salt solutions were carried out, the so-calledCoverstock Wetback test following the EDANA standard 151.0-93 with thefollowing changes, i.e. use of a blood substitute solution instead ofthe salt solution, with the following recipe:

-   1) 100 g glycerol 85%    -   100 g distilled water    -   1.8 g sodium chloride    -   0.1 g Congo Red.-   2) blood substitute solution according to 1)+5 g/l butter.    The base was a glass plate and the test was carried out as follows:

A soaking body (filter paper) is soaked with 40 g blood substitutesolution according to 1 or 2. The dwell time is two minutes. Thespecimen, either the non-woven material, the sheet material or thecombined material is disposed with its outer side onto the soaking body.A filter paper is subsequently disposed onto the specimen onto which aPE foam rubber support is disposed. The specimen is loaded with 4,000 gfor 3 minutes. The filter paper is subsequently re-weighed.

The first mentioned blood substitute solution achieved a value of lessthan 5 g for the outer non-woven material alone. The blood substitutesolution+5 g/l butter obtained a value less than 10. The barrier layermaterial and also the non-woven material including the barrier materialshowed a penetration of 0 g each. These materials are therefore highlyrepellent, in particular, for blood. 0.04 g of the blood substitutesolution and 0.02 g of the blood substitute solution with butterpenetrated through the double SMS non-woven material of Kimberly Clark.

The invention is explained in more detail below with reference to thedrawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows an inventive piece of clothing; and

FIG. 2 shows a section through a piece of clothing according to FIG. 1in the region of a reinforced zone.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A piece of clothing, e.g. an operating coat 10 comprising an outermaterial 12 which forms the clothing 10 of a three-layered polypropylenenon-woven material of SMS material with a meltblown central layer ofmicrofibers in the form of the wrap-around coat shown, presents a safeand comfortable protective piece of clothing for operations involvinglarge amounts of liquids and high risk of infection. The outer material12 has good resistance to penetrating moisture and germs, iswear-resistant, and produces nearly no fluff.

The sleeve seams (not shown) may, in particular, be provided on theupper side of the sleeves, and elastic protective bands 14 of 100% PESare disposed at the end 16 of the sleeves. The sleeves 20 are Raglansleeves which provide more freedom of movement.

A coat 10 of this type can be closed in the region of the neck 18 usinga Velcro fastener disposed in the back region. In case of a wrap-aroundcoat 10, the back part has a particularly wide overlapping to obtain twoback parts. The first and second back parts may be fastened via tiedstraps to securely fix the overlapped portion.

The lower arm 22 region and the breast and leg regions 24 may haveadditional liquid-repellent, but air-permeable reinforcements providedby a barrier layer of a non-woven sheet laminated material. Thelaminated materials provided in the reinforcing region may be laminatedmaterial connected by fusion adhesive, of polypropylene spun non-woveninherently hydrophobic or liquid repellent material and stretchedpolyethylene/calcium carbonate sheet. The lower arm reinforcement 22 andthe non-woven material are sewn at the bottom to the arm band 14 andwelded to the outer non-woven material 12 in the upper region, i.e. theelbow region 26.

The breast reinforcement 24 may be fastened to the upper 12, non-wovenmaterial of the coat 10 at individual, in particular, seven locations(e.g. three at the top, two at the bottom and two on the side). Thereinforcement 24 in the breast region may have a trapezoidal shape andbe sufficiently long to also protect the hips and legs of the personwearing it.

FIG. 2 shows a section through a piece of clothing in accordance withFIG. 1 in the region of the provided reinforcements, e.g. in the breastregion 24. Only a section of the inventive piece of clothing is shown.The outer material 12 thereby has a three-layered structure with twoouter layers 12′ and 12″, wherein the layer 12′ forms the outside of thecoat and wherein these two layers are made from a spunbond material asdescribed above, having a surface density of approximately 13 g/m². Thecentral layer 12′″ consists of a meltblown material with a surfacedensity of approximately 9 g/m² which forms a first barrier for liquidsand bacteria. The layers 12′ and 12″ have soft and fleecy visual andhaptic properties and provide comfortable wear of a piece of clothing 10of this type on the inside and outside. The breast region 24 inner sidei.e. the side 28 facing the person wearing it, has an additionalreinforcement of the non-woven sheet laminated material, which is alaminated material connected through fusion adhesive with apolypropylene spun non-woven material 13′ having a surface density ofapproximately 18 g/m² and a polyethylene sheet 13″ which is filled witha filler, i.e. calcium carbonate to generate the microporosity, whereinthe entire sheet has a surface density of approximately 18 g/m². Thefusion adhesive connecting the two layers is applied with 2 g/m². Thesheet is additionally mechanically finished, in particular, throughstretching to obtain good air permeability. The non-woven sheetlaminated material 13 of the barrier layer is thereby connected to theouter non-woven material 12 e.g. through thermal welding connections orultrasound welding. The barrier layer is liquid-proof and alsobacteria-proof, but permits passage of heat and water vapor to ensurecomfortable wear of the piece of clothing.

Further advantages and features can be extracted from the remainingapplication documents which are essential to the invention individuallyand in arbitrary combination.

1. A disposable piece of clothing, suitable for medical, chemical orbiotechnological use to protect a user wearing the clothing from liquidsor microorganisms, the clothing comprising: at least one air-permeable,hydrophobic or liquid repellent outer layer having a non-woven laminatedmaterial made from at least one meltblown layer sandwiched between twospunbond layers; and a laminated liquid-impermeable, air permeable innerbarrier layer connected, at least in sections, to regions of a side ofsaid outer layer facing the user, said barrier layer having an outerliquid impermeable, air permeable layer and an inner non-wovenhydrophobic or liquid repellent layer facing the user, wherein theclothing comprises a front part and integrally connected sleeves.
 2. Thedisposable piece of clothing of claim 1, wherein said outer layercomprises a spunbond/meltblown/spunbond (SMS) or aspunbond/meltblown/meltblown/spunbond (SMMS) laminated material.
 3. Thedisposable piece of clothing of claim 1, wherein said barrier layer isconnected to said outer layer in a material-bonding fashion.
 4. Thedisposable piece of clothing of claim 3, wherein said material-bondingcomprises glue or welding connections.
 5. The disposable piece ofclothing of claim 1, wherein said barrier layer is disposed proximatesaid sleeves or proximate lower sleeve ends in a region of user hands tobeyond user elbows and/or in a breast region of the user, wherein saidbarrier layer extends in the breast region beyond user knees.
 6. Thedisposable piece of clothing of claim 1, wherein regions of the sleevesare formed by an other material.
 7. The disposable piece of clothing ofclaim 6, where said other material is a non-woven sheet of laminatedmaterial.
 8. The disposable piece of clothing of claim 1, wherein saidsleeves are Raglan sleeves.
 9. The disposable piece of clothing of claim1, wherein seams in the clothing are folded-over seams or overlappingseams.
 10. A disposable piece of clothing, suitable for medical,chemical or biotechnological use to protect a user wearing the clothingfrom liquids or microorganisms, the clothing comprising: at least oneair-permeable, hydrophobic or liquid repellent outer layer having anon-woven laminated material made from at least one meltblown layersandwiched between two spunbond layers; and a laminatedliquid-impermeable, air permeable inner barrier layer connected, atleast in sections, to regions of a side of said outer layer facing theuser, said barrier layer having an outer air permeable, liquidimpermeable layer and an inner hydrophobic or liquid repellent non-wovenlayer facing the user, wherein the clothing comprises a front part andintegrally connected sleeves, the clothing having a water vaporpermeability of at least 2,000 g/m² at reinforced locations thereof. 11.A disposable piece of clothing, suitable for medical, chemical orbiotechnological use to protect a user wearing the clothing from liquidsor microorganisms, the clothing comprising: at least one air-permeable,hydrophobic or liquid repellent outer layer having a non-woven laminatedmaterial made from at least one meltblown layer sandwiched between twospunbond layers; and a laminated liquid-impermeable, air permeable innerbarrier layer connected, at least in sections, to regions of a side ofsaid outer layer facing the user, said barrier layer having an outer airpermeable, liquid impermeable layer and an inner hydrophobic or liquidrepellent non-woven layer facing the user, wherein the clothingcomprises a front part and integrally connected sleeves, the clothinghaving a penetration resistance to water of at least 150 cm atreinforced locations thereof.
 12. A disposable piece of clothing,suitable for medical, chemical or biotechnological use to protect a userwearing the clothing from liquids or microorganisms, the clothingcomprising: a front part having at least one air-permeable, hydrophobicor liquid repellent outer layer containing a non-woven laminatedmaterial made from at least one meltblown layer sandwiched between twospunbond layers and a laminated liquid-impermeable, air permeable innerbarrier layer connected, at least in sections, to regions of a side ofsaid outer layer facing the user, said barrier layer having an outer airpermeable, liquid impermeable layer and an inner hydrophobic or liquidrepellent non-woven layer facing the user; and sleeves integrallyconnected to said front part, said sleeves consisting essentially of alaminated liquid impermeable, air permeable barrier layer containing anouter hydrophobic or liquid repellent non-woven layer and an inner airpermeable, liquid impermeable layer facing the user.